package practicedemo16;

import java.util.Scanner;
import static java.lang.Math.sqrt;

public class practicedemo16 {
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        int x = sc.nextInt();
        if (x<2) {
            System.out.println("错误的数据类型");
        } else {
            System.out.println((int)sqrt(x));
        }
    }
}
